Muwatta Malik, Book 18, Hadith 639 (In-Book)

Yahya related to me from Malik from Abu Hazim ibn Dinar from Sahl ibn Sad as Saidi that the Messenger of Allah, may Allah bless him and grant him peace, said, "People will remain in good as long as they are quick to break the fast."

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ أَبِي حَازِمِ بْنِ دِينَارٍ، عَنْ سَهْلِ بْنِ سَعْدٍ السَّاعِدِيِّ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ لاَ يَزَالُ النَّاسُ بِخَيْرٍ مَا عَجَّلُوا الْفِطْرَ ‏" ‏ ‏.‏

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also referenced under: Book 18, Hadith 6 (USC-MSA)